The company attributed the tight supply to the "unresolved technology migration issues" of some competitors.

Hynix said the NAND flash market improved significantly during the first half of the quarter due to the demand increase from MP3 players, but started to slow down again in the second half of the quarter due to worse-than-expected sell-through of the end applications.

Hynix said its weighted average selling price for DRAM in the fourth quarter increased by 9 percent sequentially, while bit growth increased by 31 percent based on the "smooth ramp up" of 80-nm technology and accelerated volume production of fabs in Wuxi, China.

For NAND flash, although the average selling price fell by 11 percent sequentially, but bit growth of 27 percent was enough to offset the price drop, Hynix said.